How Long Should a Sentence Be?

The length of your sentence should automatically be adapted to fit the subject you are describing.

Using a long description can add a sense of relaxation and slowing time down.  Shorter sentences are quick and punchy, good for describing dramatic events and action.

You're reader will understand that you're thinking carefully about each sentence because you're consciously tackling each sentence differently.

Here are a few examples:

"The History lesson seemed, to Kevin to be dragging on forever, as Mrs Bane's voice dragged on and on, it its weary, low monotone, about the apparently fascinating life of Henry V, who seemed to Kevin, to be unhealthily and unnaturally interested in scenes of death and decay".

"The waves crashed.  The moon shone brightly. All else was silent on the deserted beach.  From the distance came the sound of thunder".

Sentence Rhythm

Using short sentences repeatedly will create choppy, staccato rhythm.  Longer sentences have more fluidity, along with a fluent rhythm.

In Summary:

Long Sentences:

Slow, descriptive or explanatory.
Creating a sense of relaxation, flow, or time slowing.
Using a long sentence can create rhythm and a fluent style.

Short Sentences:

Great for action, or dramatic lines.  For example, 'a shot rang out'.
Short sentences create quick punchy rhythm.

Sentence Structure

Once you start varying the length of your sentence you should also try varying their construction.

A simple technique is to put in the occasional adverb before the subject or verb.

For example:

"He walked carefully".

Change it to:

"Carefully he walked".

Remember to always create variety.

Removing 'he did this' or 'he did that' gets rid of all repetition and creates variation.  Instead 'he saw a picture above the fireplace' becomes, 'above the fireplace hung a picture'.

Often sentences with subject kept to the end are often called 'suspenseful', because the reader has to see who or what the subject is.  You can create effects by using these suspenseful sentences.

For example:  "Donna ran through the long crowded corridors, where her school mates stopped to stare at her, out through the big double doors at the front of the school and down the main road that led to her home".

This sentence can become more effective by putting the subject (Donna) and her verb (ran) at the end:

"Through the long-crowded corridors, where her schoolmates stopped to stare at her, out through the big double doors at the front of the school, and down the main road that led to her home Donna ran".